Monday 27 January 2014

Barden Lake at Haysden slowly drying out again as the floods recede slightly.

The water level in Barden Lake has slowly and gently dropped, and you can now walk all the way around, muddy though it is.  On the Fishing Lake by the cafe block, there were some a couple of nice Tufted Ducks, Aythya fuligula, 2 males. This bird does not have an obvious crest, but I think must still be older than a first winter juvenile, as there is no barring on the flanks. The water droplets still clinging to the feathers may indicate that the bird has recently surfaced and the crest may then be slicked down in consequence.

Other interesting ID features are the interestingly shaped head with the high forehead on a relatively narrow neck. The bill has a good solid black tip or nail (across the cross-section of the bill, looking as though it "has been dipped in ink"). There is more than a hint of a whitish stripe across the front of the bill, contrasting with the blue-grey on the rear part of the bill.  The bird is said to sit low in the water but with its tail above the surface, and I think I would agree with this from this picture to some extent - it looks as though its sitting a bit lower in the water at the moment, per haps after a dive. Deep yellow eye, perhaps slightly out of focus.  The contrast between the dark wing and the white sides is nice and distinct, a beautiful bird indeed, moving well across the water!.


On the main Gravel Pit, Barden Lake, other individuals were keeping themselves out of trouble. This one looks very much at rest, but with its eyes open! I think that the wings are most easily seen from this angle, with the two sets of primary feathers forming a valley down the back between the two wings. It also looks to me as though the flank feathers somewhat overlie the sides of the wings, giving that fringed effect to the rear of the white sides. The tail sits slightly cocked in this picture.


According to the BTO, "the rapid expansion of the Tufted Duck in Britain during the late 19th/early 20th century is probably due to the colonisation of Britain by Zebra Mussels (brought into London docks in the 1820s)".  The birds are omnivorous, feeding mainly on mussels, insects and plant material taken from the muddy bottoms of the water bodies they are on, diving anywhere between 4 - 15 metres down. It breeds better if there aren't excessive numbers of fish. 

The females show the same amount of darkening at the top of the biill, with a little light band just behind. Some of them show a scaup-like white patch at the base of the bill, although not quite so extensive, and I rather think quite a lot of them show some degree of lighter brown in that area, like the one in the duck below.



Sunday 19 January 2014

Wet but bright at Haysden


The paths were still under water, but the sun was shining, and it was actually quite warm. The Gulls and geese were showing well, but it was very busy and there were few ducks to be seen.

This gull is stabilising itself with its wings, in order to duck its head below the surf\ace in a very rapid movement. A skirt of water flies up past its head!


This one is demonstrating its STOL capabilities


and this one looks as though its just blown a huge bubble!


Further around the lake, there were some Tufted Duck, Aythya fuligola, quite a way out on the water from the bird feeding stage. The males were showing off their crests dramatically, as in the picture taken below. This bird looks as though it is riding high in the water, with the tail clearly visible. It doesn't look as though it has dived for quite a while!



Saturday 18 January 2014

Sunnier at Leybourne


Odd title, but there you go, A fair bit on gulls here. I think I'm ready to try some species-specific blog pages for gulls, that will relate to my topic pages dated at the start of the year so that I can find them more easily!

Black-headed Gulls first.


This is an adult bird just moulting onto breeding plumage, with perfect "new moons" on the folded primaries caused by the appearance of narrow white tips to the primaries at this stage. These new moons disappear in the summer, as the primaries become black-tipped!

The extent of the breeding head pattern in this bird is quite well set out already, half way through January in a mild winter to date (18.01.14), in a bird that stood out as an early moulter compared to the majority. The white eye ring is already reasonably  clear.

As an adult in winter plumage it has a dark red bill with a dark tip, not as drooping as a Med Gull. The legs are a dark red as well, and should become darker as the season progresses. I do wonder whether this due to an increasing deposition of melanin.

The light was not bad today and the mantle and coverts were a lovely attractive sea-grey colour.

A Herring Gull seen quite far away had a good black bar across the bill, quite a bit of brown on the wing, and not too much white spotting on the primaries. I couldn't see any dark tip to the tail, but if there was one there, it would certainly have been a 3rd calendar year bird, as opposed to a 4th.


Friday 10 January 2014

Scaup at Conwy

2 pairs of Red-breasted Merganser, dozens of Teal and Mallard, 30+ Canada Geese, 1 Snipe, 4+ Little Grebe, 5+ Coot, and I also managed to see one drake Scaup, although I don't think I got a photo! Many small groups of starlings rocketing over and also several Redshank on the shore.

Scaup, or Greater Scaup, Aythya marila, is a very common fully migratory duck in the Northern hemisphere, some of whom winter in the UK and a very few pairs breed in Shetland, etc.. There is a complex courtship ritual, leading to a monogamous pair bond for the season. They breed communally and the male abandons the nest to moult after the duck has laid her eggs. The duck takes care of the nest and then the young.

Aythya are all diving duck, collecting shellfish and plants etc. from the seabed as well as insects,and then eating them on the surface, Easiest to spot in the UK wintering on estuaries, including the Dee, Solway, Forth and Moray, and may be gregarious.

I saw a pair at Cliffe Pools December 2012, once they had been pointed out to me. I found this drake on my own but I had seen it posted as a possible on the board in the reception building, so I was prepared to see it. Still a good bird, and I got a good enough view to see the dark green sheen on the black head.

North Wales Coast, battered by severe storms

Amazing pair of Red-breasted Mergansers, many Common Scoters in small rafts off-shore, 1 Great Crested Grebe, 7+ Cormorants, 100+ Black-headed Gulls, 50+ Herring Gulls, 30+ Greater Black-backed Gull, at least one Common Gull, Larus canus.


This. I think, is a first winter Herring Gull from the streaky patterns on the wings and the still blackish bill, with little trace of yellow on it, and no white tip, and a dark eye. Also no sign of broadening of the white "New Moons" on the primaries. On the groyne by the Saint George viewpoint.




The greater coverts show 3 (2 and a half) rows of chevron-like blotches on the lower edge of the "wing", a much more confusing patch of blotches on the median and lesser coverts, and internal anchor-marks on the scapulars above. You can see the mid-grey on the inner part of the bill fairly clearly, particularly in the last photo. Because of the clarity of the pattern I am fairly sure it is a first winter.

I think this bird is probably a second winter bird, quite advanced perhaps. There is a lot of grey in the mantle, but no grey bar on the wing. The bill doesn't look so advanced, but there is a clear white tip to it. In this view this bird has quite a flat-topped head.


This bird in contrast is a third winter. Grey mantle, with only some remnants of brown barring on the wing, few/no obvious mirrors as yet, beak with obvious black markings across full depth of bill. Quite a lot more streaking down the neck than in the Book, but very similar to other photos on advanced websites. The eye is quite pale by now. Perhaps there is the start of a white tertial spot.


And here is an adult Herring Gull with a well-coloured bill with only a hint of black, and clear wing mirrors, a white tertial spot and no black markings on the tail. The head streaking is fairly light on this bird.


And even lighter on this one. I can't see a facial step here and the head looks quite rounded. A female perhaps:


Here is a picture of the wing mirrors on an adult with an immature bird behind. See how the immature bird is just starting a wing mirror on P6.


There were also some Greater Black-backed Gulls on the sand. Its interesting how they do tend to stick together at least to some extent. Fantastic large mirrors.


Thursday 9 January 2014

Holm oak leafminer at the services

This appeared to be Ectoedemia heringella.

Sunday 5 January 2014

Rained out again, at Leybourne

Yet another very wet day, no point in getting the telescope or camera out, so I just walked Monty around the round pond at Leybourne, betting thoroughly soaked in the process, just before dusk.

The swans, duck and coot just visible through the murk, but no gulls seen! 

Thursday 2 January 2014

Cliffe Pools on a nice day, but after low tide

Little Grebes, Great Crested Grebes, Cormorant, Lapwings, Redshanks, Shoveller, Mallard, Pintail, Gadwall, Wigeon, Teal, Coot, Common Gull, Larus canus, Black-headed Gull, Herring Gull. 

Wednesday 1 January 2014

Black-headed Gulls adults


Head patterns

Head patterns of adults are quite variable over the winter. Here we are getting the double headphones pattern.


Same bird, head turned partly towards us with both headphones still visible.



This is the same bird again, this time looking more directly in our direction. The first headphone is quite clear, the second is now on the reverse slope of the skull, except for both its lower ends.


The beak colour here is as in Ohlsen and Larsson, going towards the "concolorous maroon" of the breeding season as discussed below.

It is worth remembering that the moult into breeding plumage is only partial - relating to head and body only. The bird has to rely on the wing and tail feathers formed the previous summer for its successful performance during the breeding season.

"Those individuals who moult their hood early apparently do so every year. What is interesting though is that their moult takes place over a much longer period of time than for those individuals who acquire their full hood during the regular moult stage. Those who have a normal moult do so very quickly, up to 10 – 15% a day. This means that a full hood can be acquired in around a week. The individuals that I have seen with early head moult (see examples below) took weeks before their hood was anywhere near completion." from the excellent "Gulls to the horizon" blog.

Beak colours

The beak colour seems to be generally orange in younger birds, ranging from yellow-orange to a more reddish-orange, and always with something of a dark tip (see non-adults page). In adults the beak colours seem to vary, being a bright to moderate red in late summer through to mid-winter, and then darkening to a dark blood red (maroon) as breeding approaches, often getting as dark as the dark tip of the bill, which itself slightly lightens until the beak can be described as "concolorous maroon". However in the mid-autumn it is often really quite a bright red, perhaps much more highly coloured than the winter mid-red. This could admittedly be an effect of higher light intensities.

This is a bird in mid-autumn seen at Barden in late October 2013, showing the moderately bright red colour to the bill:


This is a bird seen near Saint George in January 2014, and you can see how the tip is getting browner from the original black.







Weblinks for Black-headed Gulls

http://bhgullsni.blogspot.co.uk/

http://guernseygulls.blogspot.co.uk/

http://www.ridibundus.gull-research.org/01cymay.html

http://gullstothehorizon.wordpress.com/2013/01/05/the-p9-conondrum/